The possible roles of vitamin E (alpha-tocopherol) in protecting photoreceptor membranes from autoxidation, in influencing pigment epithelial storage of vitamin A, and in retarding the accumulation of lipofuscin (aging pigment) in the retina were investigated. Rats were deprived of vitamin E while receivng marginal or fully adequate amounts of vitamin A for 3, 5, and 8 months. By 5 months the retinas of vitamin E-deficient rats exhibited altered outer segment membranes, loss of photoreceptor nuclei, and the accumulation in the pigment epithelium of unusually large numbers of intracellular granules showing liposuscin-specific autofluorescence. Extraordinary accumulations of aging pigment occurred also in extraocular muscle, uterus, heart, liver and brain. Vitamin A-specific autofluorescence of retinal pigment epithelium and liver were higher in vitamin E-fed compared to vitamin E-deprived rats. Thus, vitamin E probably inhibited the peroxidative loss of vitamin A in both these tissues. In addition, vitamin E protected the photoreceptor cells from membrane disintegration and retarded aging pigment formation in the retinal pigment epithelium.